Safety appliance



SAFETY APPLIANCE Filed April 25. 1929 J. KRELL 1,812,245

2 Sheets-Sheet 1 In I 4 i 12 13 7 0 6 I 4 14 a r l ri 7/////f IN vew TaR June 30, 1931. J, KRELL 1,812,245

SAFETY APPLIANCE Filed April 25. 1929 2 Sheets-Sheet 2 1 krel/ lNvNTO/QPatented June 30, 1931 JOSEPH KRELL, F BERLIN-ZEHLEIN'I'JORYF, GERMANYSA H NF E I I Application filea'n rirzs; 1929, Serial No, 358,039, andin Germany Maya, 1928.

ject of 'my'inventi'on to provide a simpleand 1 reliable's'afetyappliance which will notinterfere'with the operation ofthe machine andnot require the machine to be stopped.

To this end'I'provide a guard adaptedto 1 0 engage the "fingers of anoperator, and I so control this guard that it projects into" the path ofthe head'when the head is raised,and' is moved out of itspath and towardthe operators station when the head descends.

printing head. H I

My novel safety appliance engages with absolute Zreliability any anumber of fingers which maybe in the danger zone, and pushes them backso that they are 'not struckby the descending head. At the same timeitis not necessary to stop the machine to prevent the head from engaginga finger.

9 In reducing my'invention to practice I provide a guard which in itsinitialkposition pro jects to a short distance above the table of themachine so as toa dmit a paperor' form on which the machine prints butnot 'the oper-' ators fingers, and upon descent of the print- '3 made ofrubber'or other resilientmateri'al and is arched on its lower face sothat the lower part ofthe arched face approachesthe table of the machineand the guard perform'sa sort of rolling movement with respect to thetable,-

40 pushing back the fingers at considerable force.

In a" preferred embodiment of my invention I provide an arm ofcomparatively short length which is fulcrumed on'the printing head and alink fulcrumed on the frame of the machine and pivotally connected withthe arm so that the connection of the link and the arm moves on an arcofa circle about the fulcrum the link. This fulcrum is: preferablyarranged above and a short distanceiin front of thefulcrum of the arm onPreferably theineansjv for controlling the guard are oper'ativelyconnected the the head so that an upwardmovementis im parted to theguard which is attached to the free end "of the arm immediately upon thedescent of the printing head.

1 UNITED i It is another object ofmy invention 'to adapt the guard toprinting pads of various, widths and .tothis end I provide'means fordisplacing the fulcrum ofthe link 'on'the frame of the-machine,

It is still another object of my lnvention to renderthe guard inactivewhenthemachine 1s cleanedor inspected-and to' this end I provide meansfor fixing the guard in such inactive'position. I I shall now referenceto a machine; having a rocking printing head but it is understood thatit may also be applied to a machine'having ahead guided on a'verticalline arid'not on a'gcurve,

printing head is provided with a, printing pad Qas ,will be described,or with type for Printing-l i '1' In the accompanying drawings a machinehaving a rocking printing head andequipped with my novelsafety applianceis illustrated byway of example, L

In the drawings 'Fig. 1 is'an elevatlon of the machineviewed.

describe invention fwith land ,thatit makes no difl'ereneewhetherzthe Ifrom the front onthe operators station, 33

' Fig. 2 is a: p'lan viewof the machine, the arrow I indicating thedirection in which themachine is viewed in Fig. 1, v -Figs. '3 and taree'nd elevations viewed in the direction of th elarrow IIIin Fig. 2, andshowing the? printing head raised and I lowered, respectively, with thecontrolset for a narrow printing pad, h t

Figs. 5 and6 are similar illustrations showing the control set for awider printing .pad, Fig. 7 shows the guard in inactive. position,

Fig, 8 is adetail illustration showing the means for fixing the link ininactive position,

and viewed in the direction Fig, .7, 5

andf a Fig. 9 is ardetail illustration, drawntoa larger scaleand showingthe means for fixing the guard in inactive position. v a -Referring nowto the drawings, 1 is the frame'of'the' machine, 2 is its table, 3 is. a

guideway in the table for feeding printing plates 4 to the printingstation, 5 is a supply hopper for the printing plates, 6 is the printingstation, 7 is a ribbon moved above the printing plates, 8 is a printingarm pivotally carried on the table 2, 10 is the printing head, 11 is aprinting pad on the head, and 11 is a rubber plate on the lower face ofthe pad 11. Forms or other papers to be printed are placed on top of theribbon 7 and forced down onto the printing plates 4 by the pad 11.

12 is a. substantially U-shaped bracket having two rearwardly extendingarms 12 and secured to the front face of the printing head 10, 13 is apivot in each arm, 14 are arms pivoted on the pivots 13, 15 is a guardsecured to the free ends of the arms 14, 16, Fig. 1, is a curved linkwhich engages one of the arms 14 by a pivot 14, 16 is a boss at the endof the link 16, 17 is a pin about which the link is adapted to rock andon which it may be displaced as will be described, 16 is a projection onthe boss opposite the link 16, 17 is a boss at the upper end of anupright 18 which may be secured to the hopper 5, 19 and 20 are holes inthe boss 17 for the reception of the pin 17, and 21 is a. set screw forholding the pin in the hole 19.

As shown for a. narrow printing pad in Figs. 3 and 4, the pin 17 isinserted in the hole 19, and held by the set screw 21 in which positionthe pin 17' is at a considerable distance above the pivots 13 of thearms 14, 14, and some distance in front of such pivots. The effectivelength of the link 16 is such that with the printing head raised as inFig. 3 the guard 15 does not depend vertically from the pivots 13 but ismoved a little to the front from such vertical position.

Referring now to Figs. 5 and 6 these show the printing head 10 equippedwith a wider pad 11a. In this case a bracket 12 is provided in which thepivots 13 are further to the front than in the example illustrated inFigs. 3 and 4 and the pin 17 for the link 16 is inserted in the hole 20instead of the hole 19, and held by the set screw 21.

The lower face of the guard 15 is arched upwards, and so is its rearend. he radius of the arch is such that when the guard moves from theposition Fig. 3 into the position Fig. 4 the vertical clearance betweenthe table 2 and the lowest point of the guard 15 is very small for anyposition of the guard.

Referring now to Fig. 9, 24 is a bolt in the bracket 12 which is urgedout of its bore by a spring 23, and adapted to engage in a hole 25 ofone of the arms 14, for an object which will be described.

Before starting for a printing operation the parts are in the positionillustrated in Fig. 3 in which the guard 15 hangsdown into the path ofthe printing head 10. In this position it does not interfere with theintroduction of a form or the like but retains the fingers of theoperator. When the printing head 10 descends into printing position theguard 15 is moved toward the front and into the position Fig. 4 in whichit is moved out of the path of the printing head 10. In this position itpermits the pad 11 to engage the form on the ribbon 7. When the printingarm 8 is raised again the guard is returned to the position Fig. 3 bythe link 16 and the arms 14. If now the operator upon downward movementof the arm 8 does not remove his fingers out of the path of the printinghead 10, as shown in Fig. 3, the guard 15 upon descent of the printinghead and as shown in Fig. 4, pushes back the fingers without hurtingthem as the guard is of resilient material. Nor can the fingers becaught between the guard 15 and the table 2. If desired the guard 15might be provided with an outwardly curved extension, not shown, whichbefore the guard 15 has completed its outward stroke will assist inpushing back the fingers and still more reliably prevent jamming of thefingers between the guard and the table.

The guard must not interfere with certain operations, such as, forinstance,exchanging the pad 11 or 11a inserting anew ribbon 7 etc.Referring to Figs. 7, 8, and9, the link 16 with its boss 16 isdisplacedaxially on the pin 17 in the direction 22, 1, until the link hasreleased the pin 14, whereupon the link is thrown over into the positionFigs. 7 and 8 and moved in the direction 22 until the end of the boss 16engages the boss 18 and the projection 16 comes to bear on the top ofthe boss 18, preventing unintentional returnof the link 16. After thepin 14 has been released by the link 16 the arms 14 of the guard 15 areturned up until the spring catch 24 engages in the hole 25,

holding the guard in the position Fig. 7.

I claim:

1. A safety appliance for address printing or similar printing machineswith a printing head moving up and down, for preventing the nipping ofthe operators fingers by the descending printing head, comprising incombination a protective body, means for hanging the body in the path ofthe printing head when the printing head is raised, means pivotallysuspended from a stationary part of the machine and pivotally connectedto the hanging means for controlling the body so that during the downstroke of the printing head the body is rocked forwards, that is towardsthe person in char e and out of the path of the printing head.

2. A. safety appliance as claimed in claim 1 wherein the means forhanging the body from the printing head consists of comparatively shortarms and the means for controling the movement during the down stroke ofthe head includes a substantially long guiding link the upper end ofwhich is rotatably supported inthe frame of the machineso as to swing ina circular arc about the axis of rotation of the said link.

3. A safety appliance as claimed in claim 1 wherein the meansforcontrolling the movement of the body includes a substantially longguiding link operatively'connected at the lower end to the means forhanging'the body and having its upper end pivotally connected to theframe of the machine above and a short distance in front of the axis ofthe hanging means so that from the commencement of the downward movementof the printing head an'upward rocking move ment of the protective bodyis efi'ectedabout the pivot by which it is secured to the printing head.

1 wherein a block is carried bythe printing machine above and forwardlyof the printing head and wherein the means for controlling the movementof the protective'body includes a link, the upper end of which ispivotally and adjustably connected inthe longitudinal direction to theblock, a projecting nose extending from the upper connected end of thelink, the opposite end of the link being releasably andoperativelyconnected to the means for hanging the body to the head, the nose beingarranged so that after the release of the connection between the linkand the hanging means the link can be rocked about its pivot out of itsworking position and displaced in the longitudinal direction of itsupper pivoted end and fixed in an inoperative position with the noseupon the supporting block. 7

5. A safety appliance as claimed in claim 1, wherein a spring bolt ismounted on the printing head, theend of the bolt normally projectingslightly outwardly and wherein the means for angularly suspendingthe-body includes pivoted arms, one of said arms being provided with anaperture for receiving the spring bolt at the time the device is movedto inoperative position.

6. A safety appliance as claimed in claim 1, wherein the meansforhanging the body to the head includes pivoted arms and the means forguiding the body includes a link the lower end of which is pivoted tothe arms, a block carried with the machine and pro vided with two holeslocated side by side for receiving the upper pivot of the link, one ofthe holes being used when employing broad printing pads and the otherholes being used when employing narrow printing pads, substantially asand for the purposes set forth.-

7. A safety appliance as claimed in claim 1 wherein the protective bodyconsists of a piece of resilient material having the bot tom surface ofrelatively breadth of the direction of swing and so curved that when theprintin body rocks out of the path of the printing head the rear 4:. Asafety appliance as claimed in claim;

considerable a JOSEPH KRELL.

